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advanced mudpit as a next step towards high proteome coverage.we present a simple, time and cost efficient approach to tackle the proteome of prokaryotic organisms. to obtain large datasets of complex biological experiments high throughput and time and cost efficient methods still have to be developed and refined. in this study, we combined well approved techniques, namely elevated chromatographic temperatures, long reversed phase columns and the multidimensional protein identification technology mudpit to achieve high proteome coverage. the advanced mudpi ...201121751368
synthesis of +¦-aminobutyric acid by expressing lactobacillus brevis-derived glutamate decarboxylase in the corynebacterium glutamicum strain atcc 13032.purpose of work: purpose of this work is to synthesize +¦-aminobutyric acid by glutamate-producing species expressing lactobacillus brevis-derived glutamate decarboxylase genes, i.e. recombinant corynebacterium glutamicum strains, which directly convert endogenous l: -glutamate precursor into +¦-aminobutyric acid (gaba) through single-step fermentation. to express exogenous glutamate decarboxylase (gad) in an l: -glutamate-producing strain, lactobacillus brevis lb85, which can produce gaba, was ...201121826397
metabolic engineering of cellular transport for overproduction of the platform chemical 1,5-diaminopentane in corynebacterium glutamicum.the present work describes the development of a superior strain of corynebacterium glutamicum for diaminopentane (cadaverine) production via metabolic engineering of cellular transport processes. in c. glutamicum dap-3c, a tailor-made producer, the diaminopentane forming enzyme, lysine decarboxylase, was inhibited in vivo by its end-product, suggesting a potential bottleneck at the level of the export. the previously proposed lysine exporter lyse was shown not to be involved in diaminopentane ex ...201121821142
expression, purification, crystallization and preliminary crystallographic analysis of cg1458: a novel oxaloacetate decarboxylase from corynebacterium glutamicum.oxaloacetate decarboxylase catalyses the decarboxylation of oxaloacetate to pyruvate and co(2). recently, the corynebacterium glutamicum gene product cg1458 was determined to be a soluble oxaloacetate decarboxylase. to elucidate the mechanism of oxaloacetate decarboxylation by cg1458, recombinant cg1458 was purified and crystallized. the best crystal was grown from 0.2ôçàm mgcl(2), 0.1ôçàm bis-tris ph 6.0, 25%(w/v) polyethylene glycol 3350 using the hanging-drop method. the crystals belonged to ...201121821907
comparison between elementary flux modes analysis and 13c-metabolic fluxes measured in bacterial and plant cells.abstract:201121682932
lrp of corynebacterium glutamicum controls expression of the brnfe operon encoding the export system for l-methionine and branched-chain amino acids.corynebacterium glutamicum possesses export systems for various amino acids including brnfe, a two-component export system for l-methionine and the branched-chain amino acids l-valine, l-isoleucine and l-leucine. a gene for a putative transcriptional regulator of the lrp family is transcribed divergently to the brnfe operon and is required for l-isoleucine export. by comparing global gene expression changes due to l-isoleucine addition we revealed increased brnfe expression in response to l-isol ...201121683740
corynebacterium glutamicum rnase e/g-type endoribonuclease encoded by ncgl2281 is involved in the 5' maturation of 5s rrna.corynebacterium glutamicum has one rnase e/g ortholog and one rnase j ortholog but no rnase y. we previously reported that the c. glutamicum ncgl2281 gene encoding the rnase e/g ortholog complemented the rng::cat mutation in escherichia coli but not the rne-1 mutation. in this study, we constructed an ncgl2281 knockout mutant and found that the mutant cells accumulated 5s rrna precursor molecules. the processing of 16s and 23s rrna, trna, and tmrna was normal. primer extension analysis revealed ...201121717142
Construction of a novel sacB-based system for marker-free gene deletion in Corynebacterium glutamicum.Bacillus subtilis sacB gene with its 463bp upstream region including its native promoter has been used for marker-free gene deletion in Corynebacterium glutamicum, but the role of this upstream region is not clear. In this study, it was demonstrated that the upstream region of sacB failed to efficiently promote its expression in C. glutamicum, and the native promoter of sacB is weak in C. glutamicum. The expression level of sacB under its native promoter in C. glutamicum is not high enough for c ...201222100974
Efficient aerobic succinate production from glucose in minimal medium with Corynebacterium glutamicum.Corynebacterium glutamicum, an established industrial amino acid producer, has been genetically modified for efficient succinate production from the renewable carbon source glucose under fully aerobic conditions in minimal medium. The initial deletion of the succinate dehydrogenase genes (sdhCAB) led to an accumulation of 4.7 g l(-1) (40 mM) succinate as well as high amounts of acetate (125 mM) as by-product. By deleting genes for all known acetate-producing pathways (pta-ackA, pqo and cat) ace ...201222018023
Solution NMR structures reveal a distinct architecture and provide first structures for protein domain family PF04536.The protein family (Pfam) PF04536 is a broadly conserved domain family of unknown function (DUF477), with more than 1,350 members in prokaryotic and eukaryotic proteins. High-quality NMR structures of the N-terminal domain comprising residues 41-180 of the 684-residue protein CG2496 from Corynebacterium glutamicum and the N-terminal domain comprising residues 35-182 of the 435-residue protein PG0361 from Porphyromonas gingivalis both exhibit an a/ß fold comprised of a four-stranded ß-sheet, thre ...201122198206
Improving protein secretion of a transglutaminase-secreting Corynebacterium glutamicum recombinant strain on the basis of (13)C metabolic flux analysis.Corynebacterium glutamicum is known as a host species for amino acid production. This microorganism was recently noticed as a host that produces secreted proteins. In this study, we performed (13)C metabolic flux analysis ((13)C-MFA) on a recombinant C. glutamicum strain that secretes a heterologous transglutaminase (TGase) to improve TGase secretion. For the (13)C-MFA of a TGase-secreting C. glutamicum strain in batch cultivation, a (13)C-labeling experiment and measurement of mass isotopomer d ...201121903468
Corynebacterium glutamicum survives arsenic stress with arsenate reductases coupled to two distinct redox mechanisms.Arsenate reductases (ArsCs) evolved independently as a defence mechanism against toxic arsenate. In the genome of Corynebacterium glutamicum, there are two arsenic resistance operons (ars1 and ars2) and four potential genes coding for arsenate reductases (Cg_ArsC1, Cg_ArsC2, Cg_ArsC1' and Cg_ArsC4). Using knockout mutants, in vitro reconstitution of redox pathways, arsenic measurements and enzyme kinetics, we show that a single organism has two different classes of arsenate reductases. Cg_ArsC1 ...201122032722
deletion of the aconitase gene in corynebacterium glutamicum causes strong selection pressure for secondary mutations inactivating citrate synthase.the aconitase gene acn of corynebacterium glutamicum is regulated by four transcriptional regulators, indicating that the synthesis of this enzyme is carefully controlled. to understand the causes for this elaborate regulation, the properties of the δacn-1 deletion mutant were analyzed in detail. the mutant was glutamate auxotrophic in glucose minimal medium, showed a strong growth defect, and secreted large amounts of acetate. none of these phenotypes could be complemented by plasmid-encoded ac ...201121984793
current knowledge on isobutanol production with escherichia coli, bacillus subtilis and corynebacterium glutamicum.due to steadily rising crude oil prices great efforts have been made to develop designer bugs for the fermentative production of higher alcohols, such as 2-methyl-1-butanol, 3-methyl-1-butanol and 2-methyl-1-propanol (isobutanol), which all possess quality characteristics comparable to traditional oil based fuels. the common metabolic engineering approach uses the last two steps of the ehrlich pathway, catalyzed by 2-ketoacid decarboxylase and an alcohol dehydrogenase converting the branched cha ...201122008938
improvement of the redox balance increases l-valine production by corynebacterium glutamicum under oxygen deprivation conditions.production of l-valine under oxygen deprivation conditions by corynebacterium glutamicum lacking the lactate dehydrogenase gene ldha and overexpressing the l-valine biosynthesis genes ilvbncde was repressed. this was attributed to imbalanced cofactor production and consumption in the overall l-valine synthesis pathway: two moles of nadh was generated and two moles of nadph was consumed per mole of l-valine produced from one mole of glucose. in order to solve this cofactor imbalance, the coenzyme ...201122138982
Phenotypic characterization of Corynebacterium glutamicum using elementary modes towards synthesis of amino acids.Elementary flux mode (EFM) analysis is a powerful tool to represent the metabolic network structure and can be further utilized for flux analysis. The method enables characterization and quantification of feasible phenotypes in microbes. EFM analysis was employed to characterize the phenotype of Corynebacterium glutamicum to yield various amino acids. The metabolic network of C. glutamicum yielded 62 elementary modes by incorporating the accumulation of amino acids namely, lysine, alanine, valin ...201122132055
genetic and biochemical characterization of corynebacterium glutamicum atp phosphoribosyltransferase and its three mutants resistant to feedback inhibition by histidine.atp phosphoribosyltransferase (atp-prt) catalyzes the condensation of atp and prpp at the first step of histidine biosynthesis and is regulated by a feedback inhibition from product histidine. here, we report the genetic and biochemical characterization of such an enzyme, hisg(cg), from corynebacterium glutamicum, including site-directed mutagenesis of the histidine-binding site for the first time. gene disruption and complementation experiments showed that hisg(cg) is essential for histidine bi ...201122172596
Ethambutol-mediated cell wall modification in recombinant Corynebacterium glutamicum increases the biotransformation rates of cyclohexanone derivatives.The effects of structural modification of cell wall on the biotransformation capability by recombinant Corynebacterium glutamicum cells, expressing the chnB gene encoding cyclohexanone monooxygenase of Acinetobacter calcoaceticus NCIMB 9871, were investigated. Baeyer-Villiger oxygenation of 2-(2'-acetoxyethyl) cyclohexanone (MW 170 Da) into R-7-(2'-acetoxyethyl)-2-oxepanone was used as a model reaction. The whole-cell biotransformation followed Michaelis-Menten kinetics. The V (max) and K (S) va ...201121909677
Negative transcriptional control of biotin metabolism genes by the TetR-type regulator BioQ in biotin-auxotrophic Corynebacterium glutamicum ATCC 13032.Genomic context analysis in actinobacteria revealed that biotin biosynthesis and transport (bio) genes are co-localized in several genomes with a gene encoding a transcription regulator of the TetR protein family, now named BioQ. Comparative analysis of the upstream regions of bio genes identified the common 13-bp palindromic motif TGAAC-N3-GTTAC as candidate BioQ-binding site. To verify the role of BioQ in controlling the transcription of bio genes, a deletion in the bioQ coding region (cg2309) ...201122178235
phenol degradation activity and reusability of corynebacterium glutamicum coated with nh(2)-functionalized silica-encapsulated fe(3)o(4) nanoparticles.in this study, a novel method to immobilize and separate corynebacterium glutamicum for phenol degradation was developed using fe(3)o(4) nanoparticles (nps). the fe(3)o(4) nps were encapsulated with silica and functionalized with nh(2) groups to enhance their capacity to adsorb on the cell surface. the results showed that the nh(2)-functionalized silica-encapsulated fe(3)o(4) nps strongly adsorbed on the cell surface of c. glutamicum during 32d culture without any interruptions of their normal c ...201222093979
mechanism of increased respiration in an h(+)-atpase-defective mutant of corynebacterium glutamicum.we previously reported that a spontaneous h(+)-atpase-defective mutant of corynebacterium glutamicum, f172-8, derived from c. glutamicum atcc 14067, showed enhanced glucose consumption and respiration rates. to investigate the genome-based mechanism of enhanced respiration rate in such c. glutamicum mutants, a-1, an h(+)-atpase-defective mutant derived from c. glutamicum atcc 13032, which harbors the same point mutation as f172-8, was used in this study. a-1 showed similar fermentation profiles ...201122188772
Structure of a highly NADP+-specific isocitrate dehydrogenase.Isocitrate dehydrogenase catalyzes the first oxidative and decarboxylation steps in the citric acid cycle. It also lies at a crucial bifurcation point between CO2-generating steps in the cycle and carbon-conserving steps in the glyoxylate bypass. Hence, the enzyme is a focus of regulation. The bacterial enzyme is typically dependent on the coenzyme nicotinamide adenine dinucleotide phosphate. The monomeric enzyme from Corynebacterium glutamicum is highly specific towards this coenzyme and the su ...201121931217
Enzymatic synthesis of S-adenosylhomocysteine: immobilization of recombinant S-adenosylhomocysteine hydrolase from Corynebacterium glutamicum (ATCC 13032).Recombinant S-adenosylhomocysteine hydrolase from Corynebacterium glutamicum (CgSAHase) was covalently bound to Eupergit® C. The maximum yield of bound protein was 91% and the catalytic efficiency was 96.9%. When the kinetic results for the immobilized enzyme were compared with those for the soluble enzyme, no decrease in the catalytic efficiency of the former was detected. Both soluble and immobilized enzymes showed similar optimum pH and temperature ranges. The reuse of immobilized CgSAHase ca ...201122202964
Purification, crystallization and preliminary X-ray diffraction studies of the arsenic repressor ArsR from Corynebacterium glutamicum.ArsR is a member of the SmtB/ArsR family of metalloregulatory proteins that regulate prokaryotic arsenic-resistance operons. Here, the crystallization and preliminary X-ray diffraction studies of a cysteine-free derivative of ArsR from Corynebacterium glutamicum (CgArsR-C15/16/55S) are reported. CgArsR-C15/16/55S was expressed, purified, crystallized and X-ray diffraction data were collected to 1.86 Å resolution. The protein crystallized in a tetragonal space group (P4), with unit-cell parameter ...201122139180
Corynebacterium glutamicum whcB, a stationary phase-specific regulatory gene.The function of whcB, one of the four whiB homologues of Corynebacterium glutamicum, was assessed. Cells carrying the P(180) -whcB clone, and thus overexpressing the whcB gene, showed retarded growth, probably due to increased sensitivity to oxidants, whereas cells lacking whcB (?whcB) did not. However, growth retardation was not observed in cells with additionally whcE deleted. Furthermore, the ?whcE phenotype, characterized by slow growth and sensitivity to oxidants, was reversed in cells carr ...201122098456
Engineered Corynebacterium glutamicum as an endotoxin-free platform strain for lactate-based polyester production.The first biosynthetic system for lactate (LA)-based polyesters was previously created in recombinant Escherichia coli (Taguchi et al. 2008). Here, we have begun efforts to upgrade the prototype polymer production system to a practical stage by using metabolically engineered Gram-positive bacterium Corynebacterium glutamicum as an endotoxin-free platform. We designed metabolic pathways in C. glutamicum to generate monomer substrates, lactyl-CoA (LA-CoA), and 3-hydroxybutyryl-CoA (3HB-CoA), for t ...201122127753
genome sequence of corynebacterium glutamicum s9114, a strain for industrial production of glutamate.here we report the genome sequence of corynebacterium glutamicum s9114, an industrial producer widely used in production of glutamate in china. preliminary comparison with the sequences of the corynebacterium glutamicum strains atcc 13032 and r revealed some notable mutagenesis that might be related to the high yield of glutamate.201121994927
Physiology and global gene expression of a Corynebacterium glutamicum ?F(1)F(O)-ATP synthase mutant devoid of oxidative phosphorylation.A mutant of Corynebacterium glutamicum ATCC 13032 with a deletion of the atpBEFHAGDC genes encoding F(1)F(O)-ATP synthase was characterized. Whereas no growth was observed with acetate as sole carbon source, the ?F(1)F(O) mutant reached 47% of the growth rate and 65% of the biomass of the wild type during shake-flask cultivation in glucose minimal medium. Initially, the mutant strain showed a strongly increased glucose uptake rate accompanied by a high oxygen consumption rate and pyruvate secret ...201222050934
quantitative lipid composition of cell envelopes of corynebacterium glutamicum elucidated through reverse micelle extraction.cells of the corynebacterium-nocardia-mycobacterium group of bacteria are surrounded by an outer membrane (om) containing mycolic acids that are covalently linked to the underlying arabinogalactan-peptidoglycan complex. this om presumably acts as a permeability barrier that imparts high levels of intrinsic drug resistance to some members of this group, such as mycobacterium tuberculosis, and its component lipids have been studied intensively in a qualitative manner over the years. however, the q ...201121876124
biochemical disclosure of the mycolate outer membrane of corynebacterium glutamicum.corynebacterineae is a specific sub-order of gram-positive bacteria that includes mycobacterium tuberculosis and corynebacterium glutamicum. their cell wall is composed of a heteropolymer of peptidoglycan (pg) linked to arabinogalactan (ag), which in turn, is covalently associated to an atypical outer membrane hereafter called mycomembrane (m). this latter structure has been visualized by cryoelectron microscopy of vitreous sections but its biochemical composition is still poorly defined, thereb ...201122123248
corynebacterium glutamicum as a potent biocatalyst for the bioconversion of pentose sugars to value-added products.corynebacterium glutamicum, the industrial microbe traditionally used for the production of amino acids, proved its value for the fermentative production of diverse products through genetic/metabolic engineering. a successful demonstration of the heterologous expression of arabinose and xylose utilization genes made them interesting biocatalysts for pentose fermentation, which are the main components in lignocellulosic hydrolysates. its ability to withstand substantial amount of general growth i ...201122094976
production of minicellulosomes for the enhanced hydrolysis of cellulosic substrates by recombinant corynebacterium glutamicum.although cellulosic materials of plant origin are the most abundant utilizable biomass resource, the amino acid-producing organism corynebacterium glutamicum can not utilize these materials. here we report the engineering of a c. glutamicum strain expressing functional minicellulosomes containing chimeric endoglucanase e bound to minicbpa from clostridium cellulovorans that can hydrolyze cellulosic materials. the chimeric endoglucanase e consists of the endoglucanase e catalytic backbone of clos ...201122112952
growth independent rhamnolipid production from glucose using the non-pathogenic pseudomonas putida kt2440.abstract:201121999513
improved production of l-lysine by over-expression of meso-diaminopimelate decarboxylase enzyme of corynebacterium glutamicum in escherichia coli.the aim of this study is over-expression of meso-diaminopimelate decarboxylase enzyme (ec 4.1.1.20) and enhancement of l-lysine production rate. the c. glutamicum lysa gene which encodes a meso-diaminopimelate decarboxylase was cloned in e. coli. the cloned gene was sequenced; it encodes a 445 amino acids protein with molecular weight of 47 kd. expression of the lysa gene in e. coli resulted in an increase in meso-diaminopimelate decarboxylase activity, correlated with the presence in sodium dod ...201021848075
structural view of the regulatory subunit of aspartate kinase from mycobacterium tuberculosis.the aspartate kinase (ak) from mycobacterium tuberculosis (mtb) catalyzes the biosynthesis of aspartate family amino acids, including lysine, threonine, isoleucine and methionine. we determined the crystal structures of the regulatory subunit of aspartate kinase from mtb alone (referred to as mtbakβ) and in complex with threonine (referred to as mtbakβ-thr) at resolutions of 2.6 å and 2.0 å, respectively. mtbakβ is composed of two perpendicular non-equivalent act domains [aspartate kinase, chori ...201121976064
arabitol metabolism of corynebacterium glutamicum and its regulation by atlr.expression profiling of corynebacterium glutamicum in comparison to a derivative deficient of the transcriptional regulator atlr (previously known as sugr or mtlr) revealed eight genes showing more than fourfold higher mrna levels in the mutant. four of these are located in direct vicinity of the atlr gene, i.e., xylb, rbtt, mtld, and sixa, annotated as encoding xylulokinase, ribitol transporter, mannitol 2-dehydrogenase, and phosphohistidine phosphatase, respectively. transcriptional analysis i ...201122178972
bio-based production of chemicals, materials and fuels -corynebacterium glutamicum as versatile cell factory.since their discovery almost 60 years ago, corynebacterium glutamicum and related subspecies are writing a remarkable success story in industrial biotechnology. today, these gram-positive soil bacteria, traditionally well-known as excellent producers of l-amino acids are becoming flexible, efficient production platforms for various chemicals, materials and fuels. this development is intensively driven by systems metabolic engineering concepts integrating systems biology and synthetic biology int ...201122138494
Heterologous and homologous expression of the arginine biosynthetic argC~H cluster from Corynebacterium crenatum for improvement of L: -arginine production.The genes involved in L: -arginine biosynthesis in Corynebacterium crenatum are organized as the argCJBDFRGH cluster like in Corynebacterium glutamicum. However, the argC~H cluster of the C. crenatum SYPA 5-5, which is an industrialized L: -arginine producer, had a lethal mutation occurring in the ArgR repressor encoding gene. The argC~H cluster with an inactive argR was overexpressed in E. coli and C. crenatum. In the recombinant E. coli JM109 enzyme activities were increased, and more L: -argi ...201122009057
Impact of a new glucose utilization pathway in amino acid-producing Corynebacterium glutamicum.Corynebacterium glutamicum imports and phosphorylates glucose, fructose and sucrose by the phosphoenolpyruvate-dependent phosphotransferase carbohydrate uptake system (PTS). Recently, we have discovered how glucose can be utilized by C. glutamicum in a PTS-independent manner. PTS-independent glucose uptake is mediated by one of two inositol permeases (IolT1 or IolT2) and the second function of PTS, substrate phosphorylation, is catalyzed by one of two glucokinases (Glk or PpgK). PTS-deficient C. ...201122008639
conformational changes of the betaine transporter betp from corynebacterium glutamicum studied by pulse epr spectroscopy.the betaine transporter betp from corynebacterium glutamicum is activated by hyperosmotic stress critically depending on the presence and integrity of its sensory c-terminal domain. the conformational properties of the trimeric betp reconstituted in liposomes in the inactive state and during osmotic activation were investigated by site-directed spin labeling and electron paramagnetic resonance (epr) spectroscopy. comparison of intra- and intermolecular inter spin distance distributions obtained ...201122051018
efflux permease cgacr3-1 of corynebacterium glutamicum is an arsenite-specific antiporter.resistance to arsenite (as(iii)) by cells is generally accomplished by arsenite efflux permeases from acr3 or arsb unrelated families. we analyzed the function of three acr3 proteins from corynebacterium glutamicum, cgacr3-1, cgacr3-2, and cgacr3-3. cgacr3-1 conferred the highest level of as(iii) resistance and accumulation in vivo. cgacr3-1 was also the most active when everted membranes vesicles from escherichia coli or c. glutamicum mutants were assayed for efflux with different energy source ...201222102279
molecular characterization of prpr, the transcriptional activator of propionate catabolism in corynebacterium glutamicum.the 2-methylcitrate cycle is used to metabolize propionate in corynebacterium glutamicum. the regulator, prpr (cg0800), of the prpdbc2 operon was identified and characterized. the regulator has no similarities to the up to now known prpr regulators from other organisms. growth of a δprpr mutant revealed severe growth deficits and a prolonged lag phase if propionate was present in the medium. transcriptome analyses demonstrated the inability of the δprpr strain to induce the prpdbc2 genes in the ...201121933687
The glgB-encoded glycogen branching enzyme is essential for glycogen accumulation in Corynebacterium glutamicum.Corynebacterium glutamicum transiently accumulates glycogen as carbon capacitor during the early exponential growth phase in media containing carbohydrates. In some bacteria glycogen is synthesized by the consecutive action of ADP-glucose pyrophosphorylase (GlgC), glycogen synthase (GlgA) and glycogen branching enzyme (GlgB). GlgC and GlgA of C. glutamicum have been shown to be necessary for glycogen accumulation in this organism. However, although cg1381 has been annotated as the putative C. gl ...201121903753
Site-Directed Mutagenesis Studies on the L: -Arginine-Binding Sites of Feedback Inhibition in N-Acetyl-L: -glutamate Kinase (NAGK) from Corynebacterium glutamicum.Arginine biosynthesis in Corynebacterium glutamicum proceeds via a pathway that is controlled by arginine through feedback inhibition of NAGK, the enzyme that converts N-acetyl-L: -glutamate (NAG) to N-acety-L: -glutamy-L: -phosphate. In this study, the gene argB encoding NAGK from C. glutamicum ATCC 13032 was site-directed, and the L: -arginine-binding sites of feedback inhibition in Cglu_NAGK are described. The N-helix and C-terminal residues were first deleted, and the results indicated that ...201122101454
Biotin protein ligase from Corynebacterium glutamicum: role for growth and L: -lysine production.Corynebacterium glutamicum is a biotin auxotrophic Gram-positive bacterium that is used for large-scale production of amino acids, especially of L: -glutamate and L: -lysine. It is known that biotin limitation triggers L: -glutamate production and that L: -lysine production can be increased by enhancing the activity of pyruvate carboxylase, one of two biotin-dependent proteins of C. glutamicum. The gene cg0814 (accession number YP_225000) has been annotated to code for putative biotin protein li ...201122159614
regulation of the malic enzyme gene male by the transcriptional regulator malr in corynebacterium glutamicum.corynebacterium glutamicum is a gram-positive nonpathogenic bacterium that is used for the biotechnological production of amino acids. here, we investigated the transcriptional control of the male gene encoding malic enzyme (male) in c. glutamicum atcc13032, which is known to involve the nitrogen regulator amtr. gel shift experiments using purified regulators rama and ramb revealed binding of these regulators to the male promoter. in dna-affinity purification experiments a hitherto uncharacteriz ...201222261175
genome sequence of corynebacterium glutamicum atcc 14067, which provides insight into amino acid biosynthesis in coryneform bacteria.we report the genome sequence of corynebacterium glutamicum atcc 14067 (once named brevibacterium flavum), which is useful for taxonomy research and further molecular breeding in amino acid production. preliminary comparison with those of the reported coryneform strains revealed some notable differences that might be related to the difficulties in molecular manipulation.201222247536
engineering corynebacterium glutamicum for the production of pyruvate.a corynebacterium glutamicum strain with inactivated pyruvate dehydrogenase complex and a deletion of the gene encoding the pyruvate:quinone oxidoreductase produces about 19 mm l: -valine, 28 mm l: -alanine and about 55 mm pyruvate from 150 mm glucose. based on this double mutant c. glutamicum △acee △pqo, we engineered c. glutamicum for efficient production of pyruvate from glucose by additional deletion of the ldha gene encoding nad(+)-dependent l: -lactate dehydrogenase (ldha) and introduction ...201222228312
directed evolution and structural analysis of nadph-dependent acetoacetyl-coa reductase from ralstonia eutropha reveals two mutations responsible for enhanced kinetics.nicotinamide adenine dinucleotide phosphate (nadph)-dependent acetoacetyl-coa reductase (phab) is a key enzyme in the synthesis of poly(3-hydroxybutyrate) [p(3hb)], along with β-ketothiolase (phaa) and polyhydroxyalkanoate synthase (phac). in this study, phab from ralstonia eutropha was engineered by means of directed evolution consisting of an error-prone pcr-mediated mutagenesis and a p(3hb) accumulation-based in vivo screening system using escherichia coli. out of approximately twenty thousan ...201323913421
recognition of microbial and mammalian phospholipid antigens by nkt cells with diverse tcrs.cd1d-restricted natural killer t (nkt) cells include two major subgroups. the most widely studied are vα14jα18(+) invariant nkt (inkt) cells that recognize the prototypical α-galactosylceramide antigen, whereas the other major group uses diverse t-cell receptor (tcr) α-and β-chains, does not recognize α-galactosylceramide, and is referred to as diverse nkt (dnkt) cells. dnkt cells play important roles during infection and autoimmunity, but the antigens they recognize remain poorly understood. he ...201323307809
ornithine cyclodeaminase-based proline production by corynebacterium glutamicum.the soil bacterium corynebacterium glutamicum, best known for its glutamate producing ability, is suitable as a producer of a variety of bioproducts. glutamate is the precursor of the amino acid proline. proline biosynthesis typically involves three enzymes and a spontaneous cyclisation reaction. alternatively, proline can be synthesised from ornithine, an intermediate of arginine biosynthesis. the direct conversion of ornithine to proline is catalysed by ornithine cyclodeaminase. an ornithine o ...201323806148
rho and rnase play a central role in fmn riboswitch regulation in corynebacterium glutamicum.riboswitches are rna elements that regulate gene expression in response to their ligand. although these regulations are thought to be performed without any aid of other factors, recent studies suggested the participation of protein factors such as transcriptional termination factor rho and rnase in some riboswitch regulations. however, to what extent these protein factors contribute to the regulation was unclear. here, we studied the regulatory mechanism of the flavin mononucleotide (fmn) ribosw ...201425477389
c1 metabolism in corynebacterium glutamicum: an endogenous pathway for oxidation of methanol to carbon dioxide.methanol is considered an interesting carbon source in "bio-based" microbial production processes. since corynebacterium glutamicum is an important host in industrial biotechnology, in particular for amino acid production, we performed studies of the response of this organism to methanol. the c. glutamicum wild type was able to convert (13)c-labeled methanol to (13)co2. analysis of global gene expression in the presence of methanol revealed several genes of ethanol catabolism to be upregulated, ...201324014532
interaction sites of diviva and roda from corynebacterium glutamicum.elongation growth in actinobacteria is localized at the cell poles. this is in contrast to many classical model organisms where insertion of new cell wall material is localized around the lateral site. we previously described a role of roda from corynebacterium glutamicum in apical cell growth and morphogenesis. deletion of roda had drastic effects on morphology and growth, likely a result from misregulation of penicillin-binding proteins and cell wall precursor delivery. we identified the inter ...201525709601
a novel type of n-acetylglutamate synthase is involved in the first step of arginine biosynthesis in corynebacterium glutamicum.arginine biosynthesis in corynebacterium glutamicum consists of eight enzymatic steps, starting with acetylation of glutamate, catalysed by n-acetylglutamate synthase (nags). there are different kinds of known nagss, for example, "classical" arga, bifunctional argj, argo, and s-nags. however, since c. glutamicum possesses a monofunctional argj, which catalyses only the fifth step of the arginine biosynthesis pathway, glutamate must be acetylated by an as of yet unknown nags gene.201324138314
expression, crystallization and preliminary crystallographic study of glub from corynebacterium glutamicum.glub is a substrate-binding protein (sbp) which participates in the uptake of glutamic acid in corynebacterium glutamicum, a gram-positive bacterium. it is part of an atp-binding cassette (abc) transporter system. together with the transmembrane proteins gluc and glud and the cytoplasmic protein glua, which couples the hydrolysis of atp to the translocation of glutamate, they form a highly active glutamate-uptake system. as part of efforts to study the amino-acid metabolism, especially the metab ...201323722846
cell division in corynebacterineae.bacterial cells must coordinate a number of events during the cell cycle. spatio-temporal regulation of bacterial cytokinesis is indispensable for the production of viable, genetically identical offspring. in many rod-shaped bacteria, precise midcell assembly of the division machinery relies on inhibitory systems such as min and noc. in rod-shaped actinobacteria, for example corynebacterium glutamicum and mycobacterium tuberculosis, the divisome assembles in the proximity of the midcell region, ...201424782835
redox regulation by reversible protein s-thiolation in bacteria.low molecular weight (lmw) thiols function as thiol-redox buffers to maintain the reduced state of the cytoplasm. the best studied lmw thiol is the tripeptide glutathione (gsh) present in all eukaryotes and gram-negative bacteria. firmicutes bacteria, including bacillus and staphylococcus species utilize the redox buffer bacillithiol (bsh) while actinomycetes produce the related redox buffer mycothiol (msh). in eukaryotes, proteins are post-translationally modified to s-glutathionylated proteins ...201525852656
inactivation of the phosphoglucomutase gene pgm in corynebacterium glutamicum affects cell shape and glycogen metabolism.in corynebacterium glutamicum formation of glc-1-p (α-glucose-1-phosphate) from glc-6-p (glucose-6-phosphate) by α-pgm (phosphoglucomutase) is supposed to be crucial for synthesis of glycogen and the cell wall precursors trehalose and rhamnose. furthermore, pgm is probably necessary for glycogen degradation and maltose utilization as glucan phosphorylases of both pathways form glc-1-p. we here show that c. glutamicum possesses at least two pgm isoenzymes, the cg2800 (pgm) encoded enzyme contribu ...201323863124
ohr protects corynebacterium glutamicum against organic hydroperoxide induced oxidative stress.ohr, a bacterial protein encoded by the organic hydroperoxide resistance (ohr) gene, plays a critical role in resistance to organic hydroperoxides. in the present study, we show that the cys-based thiol-dependent ohr of corynebacterium glutamicum decomposes organic hydroperoxides more efficiently than hydrogen peroxide. replacement of either of the two cys residues of ohr by a ser residue resulted in drastic loss of activity. the electron donors supporting regeneration of the peroxidase activity ...201526121694
regulation of coenzyme a biosynthesis in the hyperthermophilic bacterium thermotoga maritima.regulation of coenzyme a (coa) biosynthesis in bacteria and eukaryotes occurs through feedback inhibition targeting type i and type ii pantothenate kinase (pank), respectively. in contrast, the activity of type iii pank is not affected by coa. as the hyperthermophilic bacterium thermotoga maritima harbors only a single type iii pank (tm-pank), here we examined the mechanisms that regulate coa biosynthesis in this organism. we first examined the enzyme responsible for the ketopantoate reductase ( ...201627161115
rapid electron transfer within the iii-iv supercomplex in corynebacterium glutamicum.complex iii in c. glutamicum has an unusual di-heme cyt. c1 and it co-purifies with complex iv in a supercomplex. here, we investigated the kinetics of electron transfer within this supercomplex and in the cyt. aa3 alone (cyt. bc1 was removed genetically). in the reaction of the reduced cyt. aa3 with o2, we identified the same sequence of events as with other a-type oxidases. however, even though this reaction is associated with proton uptake, no ph dependence was observed in the kinetics. for t ...201627682138
altered large-ring cyclodextrin product profile due to a mutation at tyr-172 in the amylomaltase of corynebacterium glutamicum.corynebacterium glutamicum amylomaltase (cgam) catalyzes the formation of large-ring cyclodextrins (lr-cds) with a degree of polymerization of 19 and higher. the cloned cgam gene was ligated into the pet-17b vector and used to transform escherichia coli bl21(de3). site-directed mutagenesis of tyr-172 in cgam to alanine (y172a) was performed to determine its role in the control of lr-cd production. both the recombinant wild-type (wt) and y172a enzymes were purified to apparent homogeneity and cha ...201222865069
crystallization and preliminary x-ray crystallographic analysis of the amylomaltase from corynebacterium glutamicum.amylomaltase (am; ec 2.4.1.25) belongs to the 4-α-glucanotransferase group of the α-amylase family. the enzyme can produce cycloamylose or large-ring cyclodextrin through intramolecular transglycosylation or cyclization reactions of α-1,4-glucan. amylomaltase from the mesophilic bacterium corynebacterium glutamicum (cgam) contains extra residues at the n-terminus for which the three-dimensional structure is not yet known. in this study, cgam was overexpressed and purified to homogeneity using de ...201323989149
phenylacetic acid catabolism and its transcriptional regulation in corynebacterium glutamicum.the industrially important organism corynebacterium glutamicum has been characterized in recent years for its robust ability to assimilate aromatic compounds. in this study, c. glutamicum strain as 1.542 was investigated for its ability to catabolize phenylacetic acid (paa). the paa genes were identified; they are organized as a continuous paa gene cluster. the type strain of c. glutamicum, atcc 13032, is not able to catabolize paa, but the recombinant strain atcc 13032/pec-k18mob2::paa gained t ...201222685150
asymmetric chromosome segregation in xanthomonas citri ssp. citri.this study was intended to characterize the chromosome segregation process of xanthomonas citri ssp. citri (xac) by investigating the functionality of the parb factor encoded on its chromosome, and its requirement for cell viability and virulence. using tap tagging we show that parb is expressed in xac. disruption of parb increased the cell doubling time and precluded the ability of xac to colonize the host citrus. moreover, xac mutant cells expressing only truncated forms of parb exhibited the ...201324339434
biosynthesis of l-sorbose and l-psicose based on c-c bond formation catalyzed by aldolases in an engineered corynebacterium glutamicum strain.the property of loose stereochemical control at aldol products from aldolases helped to synthesize multiple polyhydroxylated compounds with nonnatural stereoconfiguration. in this study, we discovered for the first time that some fructose 1,6-diphosphate aldolases (frua) and tagatose 1,6-diphosphate (taga) aldolases lost their strict stereoselectivity when using l-glyceraldehyde and synthesized not only l-sorbose but also a high proportion of l-psicose. among the aldolases tested, taga from baci ...201525888171
structural insights into a novel class of aspartate aminotransferase from corynebacterium glutamicum.aspartate aminotransferase from corynebacterium glutamicum (cgaspat) is a plp-dependent enzyme that catalyzes the production of l-aspartate and α-ketoglutarate from l-glutamate and oxaloacetate in l-lysine biosynthesis. in order to understand the molecular mechanism of cgaspat and compare it with those of other aspartate aminotransferases (aspats) from the aminotransferase class i, we determined the crystal structure of cgaspat. cgaspat functions as a dimer, and the cgaspat monomer consists of t ...201627355211
metabolic engineering of corynebacterium glutamicum for methanol metabolism.methanol is already an important carbon feedstock in the chemical industry, but it has found only limited application in biotechnological production processes. this can be mostly attributed to the inability of most microbial platform organisms to utilize methanol as a carbon and energy source. with the aim to turn methanol into a suitable feedstock for microbial production processes, we engineered the industrially important but nonmethylotrophic bacterium corynebacterium glutamicum toward the ut ...201525595770
functional characterization of a vanillin dehydrogenase in corynebacterium glutamicum.vanillin dehydrogenase (vdh) is a crucial enzyme involved in the degradation of lignin-derived aromatic compounds. herein, the vdh from corynebacterium glutamicum was characterized. the relative molecular mass (mr) determined by sds-page was ~51 kda, whereas the apparent native mr values revealed by gel filtration chromatography were 49.5, 92.3, 159.0 and 199.2 kda, indicating the presence of dimeric, trimeric and tetrameric forms. moreover, the enzyme showed its highest level of activity toward ...201525622822
direct production of organic acids from starch by cell surface-engineered corynebacterium glutamicum in anaerobic conditions.we produced organic acids, including lactate and succinate, directly from soluble starch under anaerobic conditions using high cell-density cultures of corynebacterium glutamicum displaying α-amylase (amya) from streptococcus bovis 148 on the cell surface. notably, reactions performed under anaerobic conditions at 35 and 40°c, which are higher than the optimal growth temperature of 30°c, showed 32% and 19%, respectively, higher productivity of the organic acids lactate, succinate, and acetate co ...201324342107
whole cell biotransformation for reductive amination reactions.whole cell biotransformation systems with enzyme cascading increasingly find application in biocatalysis to complement or replace established chemical synthetic routes for production of, e.g., fine chemicals. recently, we established an escherichia coli whole cell biotransformation system for reductive amination by coupling a transaminase and an amino acid dehydrogenase with glucose catabolism for cofactor recycling. transformation of 2-keto-3-methylvalerate to l-isoleucine by e. coli cells was ...201324406456
transcriptional cross-regulation between gram-negative and gram-positive bacteria, demonstrated using argp-argo of escherichia coli and lysg-lyse of corynebacterium glutamicum.the protein-gene pairs argp-argo of escherichia coli and lysg-lyse of corynebacterium glutamicum are orthologous, with the first member of each pair being a lysr-type transcriptional regulator and the second its target gene encoding a basic amino acid exporter. whereas lyse is an exporter of arginine (arg) and lysine (lys) whose expression is induced by arg, lys, or histidine (his), argo exports arg alone, and its expression is activated by arg but not lys or his. we have now reconstituted in e. ...201222904281
destabilized eyfp variants for dynamic gene expression studies in corynebacterium glutamicum.fluorescent reporter proteins are widely used for the non-invasive monitoring of gene expression patterns, but dynamic measurements are hampered by the extremely high stability of gfp and homologue proteins. in this study, we used ssra-mediated peptide tagging for the construction of unstable variants of the gfp derivative eyfp (enhanced yellow fluorescent protein) and applied those for transient gene expression analysis in the industrial platform organism corynebacterium glutamicum.201222938655
the tetr-type transcriptional repressor rolr from corynebacterium glutamicum regulates resorcinol catabolism by binding to a unique operator, rolo.the rol (designated for resorcinol) gene cluster rolrhmd is involved in resorcinol catabolism in corynebacterium glutamicum, and rolr is the tetr-type regulator. in this study, we investigated how rolr regulated the transcription of the rol genes in c. glutamicum. the transcription start sites and promoters of rolr and rolhmd were identified. quantitative reverse transcription-pcr and promoter activity analysis indicated that rolr negatively regulated the transcription of rolhmd and of its own g ...201222706057
biochemical and molecular characterization of the gentisate transporter genk in corynebacterium glutamicum.gentisate (2,5-dihydroxybenzoate) is a key ring-cleavage substrate involved in various aromatic compounds degradation. corynebacterium glutamicum atcc13032 is capable of growing on gentisate and genk was proposed to encode a transporter involved in this utilization by its disruption in the restriction-deficient mutant res167. its biochemical characterization by uptake assay using [(14)c]-labeled gentisate has not been previously reported.201222808015
two-component signal transduction in corynebacterium glutamicum and other corynebacteria: on the way towards stimuli and targets.in bacteria, adaptation to changing environmental conditions is often mediated by two-component signal transduction systems. in the prototypical case, a specific stimulus is sensed by a membrane-bound histidine kinase and triggers autophosphorylation of a histidine residue. subsequently, the phosphoryl group is transferred to an aspartate residue of the cognate response regulator, which then becomes active and mediates a specific response, usually by activating and/or repressing a set of target ...201222539022
characterization of oxyr as a negative transcriptional regulator that represses catalase production in corynebacterium diphtheriae.corynebacterium diphtheriae and corynebacterium glutamicum each have one gene (cat) encoding catalase. in-frame δcat mutants of c. diphtheriae and c. glutamicum were hyper-sensitive to growth inhibition and killing by h(2)o(2). in c. diphtheriae c7(β), both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. prototypic oxyr in escherichia coli senses oxidative stress and it activates katg transcription and catalase produc ...201222438866
comprehensive analysis of the corynebacterium glutamicum transcriptome using an improved rnaseq technique.the use of rnaseq to resolve the transcriptional organization of an organism was established in recent years and also showed the complexity and dynamics of bacterial transcriptomes. the aim of this study was to comprehensively investigate the transcriptome of the industrially relevant amino acid producer and model organism corynebacterium glutamicum by rnaseq in order to improve its genome annotation and to describe important features for transcription and translation.201324341750
modulation of global low-frequency motions underlies allosteric regulation: demonstration in crp/fnr family transcription factors.allostery is a fundamental process by which ligand binding to a protein alters its activity at a distinct site. there is growing evidence that allosteric cooperativity can be communicated by modulation of protein dynamics without conformational change. the mechanisms, however, for communicating dynamic fluctuations between sites are debated. we provide a foundational theory for how allostery can occur as a function of low-frequency dynamics without a change in structure. we have generated coarse ...201324058293
complex regulation of the phosphoenolpyruvate carboxykinase gene pck and characterization of its gntr-type regulator iolr as a repressor of myo-inositol utilization genes in corynebacterium glutamicum.dna affinity chromatography with the promoter region of the corynebacterium glutamicum pck gene, encoding phosphoenolpyruvate carboxykinase, led to the isolation of four transcriptional regulators, i.e., rama, gntr1, gntr2, and iolr. determination of the phosphoenolpyruvate carboxykinase activity of the δrama, δgntr1 δgntr2, and δiolr deletion mutants indicated that rama represses pck during growth on glucose about 2-fold, whereas gntr1, gntr2, and iolr activate pck expression about 2-fold irres ...201323873914
genr, an iclr-type regulator, activates and represses the transcription of gen genes involved in 3-hydroxybenzoate and gentisate catabolism in corynebacterium glutamicum.the genes required for 3-hydroxybenzoate and gentisate catabolism in corynebacterium glutamicum are closely clustered in three operons. genr, an iclr-type regulator, can activate the transcription of genkh and gendfm operons in response to 3-hydroxybenzoate and gentisate, and it can repress its own expression. footprinting analyses demonstrated that genr bound to four sites with different affinities. two genr-binding sites (dfmn01 and dfmn02) were found to be located between positions --41 and - ...201323354754
l-citrulline production by metabolically engineered corynebacterium glutamicum from glucose and alternative carbon sources.l-citrulline plays an important role in human health and nutrition and is an intermediate of the l-arginine biosynthetic pathway. l-citrulline is a by-product of l-arginine production by corynebacterium glutamicum. in this study, c. glutamicum was engineered for overproduction of l-citrulline as major product without l-arginine being produced as by-product. to this end, l-arginine biosynthesis was derepressed by deletion of the arginine repressor gene argr and conversion of l-citrulline towards ...201426267114
a chromosomally encoded t7 rna polymerase-dependent gene expression system for corynebacterium glutamicum: construction and comparative evaluation at the single-cell level.corynebacterium glutamicum has become a favourite model organism in white biotechnology. nevertheless, only few systems for the regulatable (over)expression of homologous and heterologous genes are currently available, all of which are based on the endogenous rna polymerase. in this study, we developed an isopropyl-β-d-1-thiogalactopyranosid (iptg)-inducible t7 expression system in the prophage-free strain c. glutamicum mb001. for this purpose, part of the de3 region of escherichia coli bl21(de3 ...201425488698
metabolic engineering of pseudomonas sp. strain vlb120 as platform biocatalyst for the production of isobutyric acid and other secondary metabolites.over the recent years the production of ehrlich pathway derived chemicals was shown in a variety of hosts such as escherichia coli, corynebacterium glutamicum, and yeast. exemplarily the production of isobutyric acid was demonstrated in escherichia coli with remarkable titers and yields. however, these examples suffer from byproduct formation due to the fermentative growth mode of the respective organism. we aim at establishing a new aerobic, chassis for the synthesis of isobutyric acid and othe ...201424397404
reactions of cg10062, a cis-3-chloroacrylic acid dehalogenase homologue, with acetylene and allene substrates: evidence for a hydration-dependent decarboxylation.cg10062 is a cis-3-chloroacrylic acid dehalogenase (cis-caad) homologue from corynebacterium glutamicum with an unknown function and an uninformative genomic context. it shares 53% pairwise sequence similarity with cis-caad including the six active site amino acids (pro-1, his-28, arg-70, arg-73, tyr-103, and glu-114) that are critical for cis-caad activity. however, cg10062 is a poor cis-caad: it lacks catalytic efficiency and isomer specificity. two acetylene compounds (propiolate and 2-butyno ...201525894805
unraveling the kinetic diversity of microbial 3-dehydroquinate dehydratases of shikimate pathway.3-dehydroquinate dehydratase (dhqase) catalyzes the conversion of 3-dehydroquinic acid to 3-dehydroshikimic acid of the shikimate pathway. in this study, 3180 prokaryotic genomes were examined and 459 dhqase sequences were retrieved. based on sequence analysis and their original hosts, 38 dhqase genes were selected for chemical synthesis. the selected dhqases were translated into new dna sequences according to the genetic codon usage bias by both escherichia coli and corynebacterium glutamicum. ...201525852984
metabolic engineering of corynebacterium glutamicum for enhanced production of 5-aminovaleric acid.5-aminovaleric acid (5ava) is an important five-carbon platform chemical that can be used for the synthesis of polymers and other chemicals of industrial interest. enzymatic conversion of l-lysine to 5ava has been achieved by employing lysine 2-monooxygenase encoded by the davb gene and 5-aminovaleramidase encoded by the dava gene. additionally, a recombinant escherichia coli strain expressing the davb and dava genes has been developed for bioconversion of l-lysine to 5ava. to use glucose and xy ...201627717386
systems metabolic engineering of corynebacterium glutamicum for the production of the carbon-5 platform chemicals 5-aminovalerate and glutarate.the steadily growing world population and our ever luxurious life style, along with the simultaneously decreasing fossil resources has confronted modern society with the issue and need of finding renewable routes to accommodate for our demands. shifting the production pipeline from raw oil to biomass requires efficient processes for numerous platform chemicals being produced with high yield, high titer and high productivity.201627618862
characterization of 3-phosphoglycerate kinase from corynebacterium glutamicum and its impact on amino acid production.corynebacterium glutamicum cg1790/pgk encodes an enzyme active as a 3-phosphoglycerate kinase (pgk) (ec 2.7.2.3) catalyzing phosphoryl transfer from 1,3-biphosphoglycerate (bpg) to adp to yield 3-phosphoglycerate (3-pg) and atp in substrate chain phosphorylation.201424593686
systems metabolic engineering of corynebacterium glutamicum for production of the chemical chaperone ectoine.the stabilizing and function-preserving effects of ectoines have attracted considerable biotechnological interest up to industrial scale processes for their production. these rely on the release of ectoines from high-salinity-cultivated microbial producer cells upon an osmotic down-shock in rather complex processor configurations. there is growing interest in uncoupling the production of ectoines from the typical conditions required for their synthesis, and instead design strains that naturally ...201324228689
biosynthesis of trans-4-hydroxyproline by recombinant strains of corynebacterium glutamicum and escherichia coli.trans-4-hydroxy-l-proline (trans-hyp), one of the hydroxyproline (hyp) isomers, is a useful chiral building block in the production of many pharmaceuticals. although there are some natural biosynthetic pathways of trans-hyp existing in microorganisms, the yield is still too low to be scaled up for industrial applications. until now the production of trans-hyp is mainly from the acid hydrolysis of collagen. due to the increasing environmental concerns on those severe chemical processes and compli ...201424885047
complete genome sequence, lifestyle, and multi-drug resistance of the human pathogen corynebacterium resistens dsm 45100 isolated from blood samples of a leukemia patient.corynebacterium resistens was initially recovered from human infections and recognized as a new coryneform species that is highly resistant to antimicrobial agents. bacteremia associated with this organism in immunocompromised patients was rapidly fatal as standard minocycline therapies failed. c. resistens dsm 45100 was isolated from a blood culture of samples taken from a patient with acute myelocytic leukemia. the complete genome sequence of c. resistens dsm 45100 was determined by pyrosequen ...201222524407
peptidoglycan from fermentation by-product triggers defense responses in grapevine.plants are constantly under attack from a variety of microorganisms, and rely on a series of complex detection and response systems to protect themselves from infection. here, we found that a by-product of glutamate fermentation triggered defense responses in grapevine, increasing the expression of defense response genes in cultured cells, foliar chitinase activity, and resistance to infection by downy mildew in leaf explants. to identify the molecule that triggered this innate immunity, we frac ...201425427192
screening currency notes for microbial pathogens and antibiotic resistance genes using a shotgun metagenomic approach.fomites are a well-known source of microbial infections and previous studies have provided insights into the sojourning microbiome of fomites from various sources. paper currency notes are one of the most commonly exchanged objects and its potential to transmit pathogenic organisms has been well recognized. approaches to identify the microbiome associated with paper currency notes have been largely limited to culture dependent approaches. subsequent studies portrayed the use of 16s ribosomal rna ...201526035208
accelerated pentose utilization by corynebacterium glutamicum for accelerated production of lysine, glutamate, ornithine and putrescine.because of their abundance in hemicellulosic wastes arabinose and xylose are an interesting source of carbon for biotechnological production processes. previous studies have engineered several corynebacterium glutamicum strains for the utilization of arabinose and xylose, however, with inefficient xylose utilization capabilities. to improve xylose utilization, different xylose isomerase genes were tested in c. glutamicum. the gene originating from xanthomonas campestris was shown to have the hig ...201223164409
optimization of the ipp precursor supply for the production of lycopene, decaprenoxanthin and astaxanthin by corynebacterium glutamicum.the biotechnologically relevant bacterium corynebacterium glutamicum, currently used for the million ton-scale production of amino acids for the food and feed industries, is pigmented due to synthesis of the rare cyclic c50 carotenoid decaprenoxanthin and its glucosides. the precursors of carotenoid biosynthesis, isopenthenyl pyrophosphate (ipp) and its isomer dimethylallyl pyrophosphate, are synthesized in this organism via the methylerythritol phosphate (mep) or non-mevalonate pathway. termina ...201425191655
single-domain peptidyl-prolyl cis/trans isomerase fkpa from corynebacterium glutamicum improves the biomass yield at increased growth temperatures.peptidyl-prolyl cis/trans isomerases (ppiases) catalyze the rate-limiting protein folding step at peptidyl bonds preceding proline residues and were found to be involved in several biological processes, including gene expression, signal transduction, and protein secretion. representative enzymes were found in almost all sequenced genomes, including corynebacterium glutamicum, a facultative anaerobic gram-positive and industrial workhorse for the production of amino acids. in c. glutamicum, a pre ...201526341203
role of corynebacterium glutamicum spra encoding a serine protease in glxr-mediated global gene regulation.the global regulator glxr of corynebacterium glutamicum is involved in many cellular activities. considering its role, the glxr protein likely interacts with other proteins to obtain, maintain, and control its activity. to isolate proteins interacting with glxr, we used a two-hybrid system with glxr as the bait. subsequently, the partner, a subtilisin-like serine protease, was isolated from a c. glutamicum genomic library. unlike glxr, which showed constitutive expression, the expression of spra ...201424691519
characterization and molecular mechanism of arop as an aromatic amino acid and histidine transporter in corynebacterium glutamicum.corynebacterium glutamicum is equipped with abundant membrane transporters to adapt to a changing environment. many amino acid transporters have been identified in c. glutamicum, but histidine uptake has not been investigated in detail. here, we identified the aromatic amino acid transporter encoded by arop as a histidine transporter in c. glutamicum by a combination of the growth and histidine uptake features. characterization of histidine uptake showed that arop has a moderate affinity for his ...201324056108
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